In Wednesday’s New York Times, I wrote about two experimental projects in California to store solar energy produced by photovoltaic rooftop arrays:

In the garage of Peter Rive’s San Francisco home is a battery pack. It is not connected to Mr. Rive’s electric Tesla Roadster sports car, but to the power grid.

The California Public Utilities Commission has awarded $1.8 million to Mr. Rive’s company, SolarCity, a residential photovoltaic panel installer, to research the feasibility of storing electricity generated by rooftop solar arrays in batteries.

As rooftop solar systems provide a growing percentage of electricity to California’s grid, regulators and utilities are increasingly concerned about how to balance the intermittent nature of that power with demand.

One possible solution is to store energy generated by solar arrays in batteries and other systems and then feed that electricity to the grid when, say, a cloudy day results in a drop in power production. And when demand peaks, electricity generated from renewable sources could be dispatched from batteries rather than fossil-fuel burning power plants.

“As soon as distributed solar starts providing 5 to 10 percent of demand, its intermittent nature will need to be addressed,” said Mr. Rive, who is SolarCity’s co-founder and chief operating officer.

SolarCity is teaming with Tesla Motors, the Silicon Valley electric car company run by Mr. Rive’s cousin, Elon Musk, and the University of California, Berkeley, to study how to integrate solar arrays and off-the-shelf Tesla lithium-ion battery backs into the grid. SolarCity plans to put such systems in six homes.

“We think in the years ahead this will be the default way that solar is installed,” Mr. Rive said. “Getting the costs down, though, is not going to be an easy task.”

Homeowners could potentially benefit by tapping batteries at hours when electricity rates are high or using them to provide backup power if the grid goes down.

The research has just begun, and at the moment SolarCity is testing the impact of charging and discharging electricity from the Tesla battery pack in Mr. Rive’s garage. His roof sports a three-kilowatt solar array.

“We’re at the point now where we can direct the battery to charge and discharge at specific times by sending a signal over the Internet,” Mr. Rive said.

Included in the $14.6 million awarded for solar energy storage research by the utilities commission was $1.9 million to SunPower for a project that will store in ice and batteries electricity generated by solar arrays at Target stores.

SunPower, a Silicon Valley solar panel manufacturer and power plant developer, will work with Ice Energy, a Colorado company that makes systems that use electricity when rates are low to form ice. When rates are high, air conditioning refrigerant is cooled by the melting ice rather than by an electricity-hogging compressor.

The Ice Bear system and a solar array will be installed at one Target store while battery packs will be used at two other stores in California.

Photo: The White House

In my new Green State column on Grist, I attend President Obama’s speech at a Silicon Valley solar panel factory:

Silicon Valley in the Internet age has not made for great presidential photo ops. The Valley’s computer-chip factories were off-shored decades ago and (Google excepted) the software giants that supplanted hardware companies just didn’t have the same pizzazz — T-shirted geeks writing code can’t compete with guys and gals in bunny suits tending big futuristic machines.

The rise of green tech has changed all that. The Valley is back in the business of building stuff — solar panels, electric cars, fuel cells, and various energy efficient widgets and gadgets.

And so when President Obama’s helicopter landed Wednesday morning at Solyndra, a solar module maker, a television-ready tableau awaited — a huge American flag hung in an unfinished factory, shiny high-tech thin-film solar panels were on display and workers in hard hats mingled with an audience of some 200 engineers, scientists, venture capitalists, and California’s patron saint of green tech PR events, Governor Arnold Schwarzenegger.

“We’ve got to go back to making things. We’ve got to go back to exports. We’ve got to go back to innovation,” said Obama on Wednesday in Fremont as Solyndra employees snapped photos with their iPhones.

“The true engine of economic growth will always be companies like Solyndra, will always be America’s businesses,” he continued. “But that doesn’t mean the government can just sit on the sidelines. Government still has the responsibility to help create the conditions in which students can gain an education so they can work at Solyndra, and entrepreneurs can get financing so they can start a company, and new industries can take hold.”

It’s an apt choice of words, for the fortunes of green tech startups like Solyndra have become entwined with the government as the Obama administration attempts to jumpstart a transition to a clean energy economy. The sprawling solar module plant we’re standing in — its construction is employing 3,000 workers — is being financed thanks in large part to a $535 million loan guarantee the Department of Energy granted to Solyndra last year.

photo: Todd Woody

In a story I wrote with Clifford Krauss in Monday’s New York Times, I look at how the San Francisco Bay Area has is scrambling to prepare for the arrival of mass-market electric cars later this year:

SAN FRANCISCO — If electric cars have any future in the United States, this may be the city where they arrive first.

The San Francisco building code will soon be revised to require that new structures be wired for car chargers. Across the street from City Hall, some drivers are already plugging converted hybrids into a row of charging stations.

In nearby Silicon Valley, companies are ordering workplace charging stations in the belief that their employees will be first in line when electric cars begin arriving in showrooms. And at the headquarters of Pacific Gas and Electric, utility executives are preparing “heat maps” of neighborhoods that they fear may overload the power grid in their exuberance for electric cars.

“There is a huge momentum here,” said Andrew Tang, an executive at P.G.& E.

As automakers prepare to introduce the first mass-market electric cars late this year, it is increasingly evident that the cars will get their most serious tryout in just a handful of places. In cities like San Francisco, Portland, Ore., and San Diego, a combination of green consciousness and enthusiasm for new technology seems to be stirring public interest in the cars.

The first wave of electric car buying is expected to begin around December, when Nissan introduces the Leaf, a five-passenger electric car that will have a range of 100 miles on a fully charged battery and be priced for middle-class families.

Several thousand Leafs made in Japan will be delivered to metropolitan areas in California, Arizona, Washington state, Oregon and Tennessee. Around the same time, General Motors will introduce the Chevrolet Volt, a vehicle able to go 40 miles on electricity before its small gasoline engine kicks in.

“This is the game-changer for our industry,” said Carlos Ghosn, Nissan’s president and chief executive. He predicted that 10 percent of the cars sold would be electric vehicles by 2020.

photo: eSolar

In Sunday’s Los Angeles Times, I write about how the rise of green technology is changing the way Silicon Valley venture capitalists do business:

Silicon Valley venture capitalists have always been about inventing the future — taking a wild idea, nurturing it with cash and creativity and giving birth to new products, companies and industries we once couldn’t imagine and now can’t conceive of living without: the Web, Google, the iPhone, Twitter.

But as green technology becomes the latest tech wave to break from the nation’s entrepreneurial epicenter, it’s now all about companies reinventing the past. Solar power companies, electric car start-ups and algae biofuel ventures aim to remake century-old trillion-dollar industries on a global scale.

Venture capitalists poured $4 billion into green-tech start-ups in 2008 — nearly 40% of all tech investments in the U.S., according to a survey by PricewaterhouseCoopers. Green-tech investment plunged in the first half of 2009 to $513 million as the recession dragged on, but there are signs of a rebound: Silicon Valley’s Khosla Ventures announced this month that it had raised $1.1 billion — the biggest first-time fund in a decade — that would be largely devoted to investing in green-tech start-ups, many in Southern California.

But green-tech companies face unique challenges, including global markets, tough technological hurdles and a future shaped by government incentives and regulatory policy. Those challenges are changing the game on Sand Hill Road.

“If you’re starting a Web 2.0 company, your basic needs are personnel and servers — there is no physical product, no manufacturing capacity, no inventory, no steel in the ground,” VantagePoint’s Salzman said, referring to software-based companies that provide services over the Internet.

photo: Think

Norwegian electric car company Think announced Thursday that it will open a factory in the United States in 2010 to produce its City urban runabout.

Think CEO Richard Canny, a former Ford executive, is in Ann Arbor, Mich., this week meeting with officials from eight states vying for the factory. But don’t put in your order just yet – only 2,500 cars will roll off the assembly line the first year and they will be reserved for demonstration projects and fleet sales.

“The U.S. is quickly overtaking Europe as an attractive market for EVs and is an ideal location to engineer and build EVs,” Canny said in a statement. “We see ourselves playing a small but potentially growing role in re-inventing the U.S. auto industry by bringing back new manufacturing jobs to the U.S.” Think has not yet responded to Green Wombat’s inquiry about which states, other than Michigan, is in talks with the company for the factory.

How Think will finance its North American expansion remains an open question. Just three months ago the company was teetering on the edge of bankruptcy as the global financial crisis cut off capital and forced Think to idle its Norwegian factory and lay off workers. The company obtained $5.7 million interim financing in January and recalled some workers. A report on Treehugger Thursday cited sources that said Think was contemplating relocating to Sweden or the U.K.

Think spokeswoman Katinka Von Der Lippe told Green Wombat on Thursday that the interim financing has been extended but that the company is still seeking a new infusion of capital to resume full production of the City, a two-seater that goes 112 miles on a charge with a top speed of about 62 miles per hour. Update: Think’s U.S. spokesman, Brendan Prebo, tells Green Wombat that Think will raise most of the new capital from its existing European and U.S. investors, which include General Electric (GE), so it can resume full production of the City in Norway.

The company said that it will apply for a low-interest loan from the U.S. Department of Energy under its Advanced Technology Vehicle Manufacturing program to help pay for the factory. Prebo declined to reveal the size of the DOE loan the company will seek but noted it “will be a substantial investment for Think” but small compared to what some of the big automakers want.

After the first-year startup phase, the U.S. factory will initially employ 300 workers and produce 16,000 cars annually, according to Think. Capacity would eventually be expanded to 60,000 cars and a workforce of 900. A research and development center will employ about 70 people.

But calling a Think facility a factory is somewhat misleading. It’s really an assembly plant and the one Green Wombat visited in 2007 in Aurskog, Norway, was more Ikea than Henry Ford, with plastic-bodied Think City models quietly gliding through clean well-lighted spaces.

The question for Think, Tesla Motors other EV startups is whether they can gain a foothold in the market before the major players big-foot them with their own electric and plug-in electric cars. Ford (F), General Motors (GM), Honda (HMC), Toyota (TM), Renault-Nissan and other global automakers all are accelerating plans to introduce electric vehicles.

Thursday’s announcement follows the formation of Think North America, unveiled in April 2008 at Fortune’s Brainstorm Green conference. A bicoastal group of venture capital firms – Silicon Valley’s Kleiner Perkins Caufield & Byers and Boston’s Rockport Capital Partners – signed on as lead investors.

Monday night, Green Wombat swung by SF Green, one of a growing number of green tech networking events sprouting up around San Francisco and Silicon Valley. The draw – beyond drinks with a standing-room-only crowd of bright-eyed twenty-and-thirtysomethings in a San Francisco art gallery – was the appearance of leading venture capitalist Ray Lane of Kleiner Perkins Caufield & Byers and Darryl Siry of Tesla Motors, maker of the Roadster electric supercar.

Siry, Tesla’s vp of sales, marketing & service, said five of the $100,000 Roadsters have rolled off the assembly line so far with one car tooling around Los Angeles, and others in the Bay Area and London. By year’s end, Tesla, which has been wrestling with drive train problems, should have more than 100 cars on Bay Area roads, home to many the company’s tech titan customers.

Tesla has raised $145 million, Siry noted, and will do another round before an IPO. The Roadster will always be a limited production marquee car but to mass produce its next vehicle, a five-seat sports sedan code-named White Star, Tesla will need that IPO or project financing. Siry also sketched a future where Tesla might supply electric drive trains to automakers in exchange for project financing.

“Tesla is a tech company wrapped in an automotive brand,” he said at the event co-sponsored by VentureBeat.

Lane and Kleiner Perkins have gone beyond investing in electric car companies to running one. Lane is chairman of Think North America, the U.S. arm of Norwegian electric carmaker Think Global. Kleiner and Rockport Capital took a 50 percent stake in the North American operation, which launched last month.

The Think and Fisker investments are emblematic of a new direction for VCs who have jumped into the green tech game. Unlike the first dot-com era or even the current Web 2.0 age, there’s no quick exit on the horizon for investments in green tech companies that may be years away from producing a product and require hundreds of millions, if not billions, in project financing to build car factories or solar energy power plants.

Lane compared investing in green tech to the long-term horizon needed for investing in biotech startups, where the key is to hit milestones that allow investors to calculate valuations.

Kleiner is also an investor in solar power plant startup Ausra. “Steel prices are killing us,” Lane said. Ausra’s power plants consist of hundred of acres of mirrors mounted on steel frames. “With Ausra, we [calculate] we could deliver solar thermal electricity at 12 cents a kilowatt-hour. But with steel prices, who knows?”

A shortage of qualified green tech workers has become an issue, according to Lane. The nascent solar power plant business relies on recruiting engineers and project developers from the carbon-based industry. “Talented people in project development at companies like Bechtel are maxed out for years on building projects,” he said.

“Years ago we came to the conclusion that global warming was a problem, it was an urgent problem and the need for action is now. The problem appears to be worse and more imminent today, and the need to take action sooner and take more significant action is greater than ever before” — PG&E Chairman and CEO Peter Darbee

The head of one of the nation’s largest utilities seemed to be channeling Al Gore on Tuesday when he met with a half-dozen environmental business writers, including Green Wombat, in the PG&E (PCG) boardroom in downtown San Francisco. While a lot of top executives talk green these days, for Darbee green has become the business model, one that represents the future of the utility industry in a carbon-constrained age.

As Katherine Ellison wrote in a feature story on PG&E that appeared in the final issue of Business 2.0 magazine last September, California’s large utilities — including Southern California Edison (EIX) and San Diego Gas & Electric (SRE) — are uniquely positioned to make the transition to renewable energy and profit from green power.

First of all, they have no choice. State regulators have mandated that California’s investor-owned utilities obtain 20 percent of their electricity from renewable sources by 2010 with a 33 percent target by 2020. Regulators have also prohibited the utilities from signing long-term contracts for dirty power – i.e. with the out-of-state coal-fired plants that currently supply 20 percent of California’s electricity. Second, PG&E and other California utilities profit when they sells less energy and thus emit fewer greenhouse gases. That’s because California regulators “decouple” utility profits from sales, setting their rate of return based on things like how well they encourage energy efficiency or promote green power.

Still, few utility CEOs have made green a corporate crusade like Darbee has since taking the top job in 2005. And the idea of a staid regulated monopoly embracing technological change and collaborating with the likes of Google (GOOG) and electric car company Tesla Motors on green tech initiatives still seems strange, if not slightly suspicious, to some Northern Californians, especially in left-leaning San Francisco where PG&E-bashing is local sport.

In a wide-ranging conversation, Darbee, 54, sketched sketched a future where being a successful utility is less about building big centralized power plants that sit idle until demand spikes and more about data management – tapping diverse sources of energy — from solar, wind and waves to electric cars — and balancing supply and demand through a smart grid that monitors everything from your home appliances to where you plugged in your car. “I love change, I love innovation,” says Darbee, who came to PG&E after a career in telecommunications and investment banking.

Renewable energy

“On renewable energy what we’ve seen is the market is thin,” says Darbee. “Demand just from ourselves is greater than supply in terms of reliable, well-funded companies that can provide the service.”

PG&E so far has signed power purchase agreements with three solar startups — Ausra, BrightSource Energy and Solel — for up to 1.6 gigawatts of electricity to be produced by massive solar power plants. Each company is deploying a different solar thermal technology and uncertainty over whether the billion-dollar solar power stations will ultimately be built has prompted PG&E to consider jumping into the Big Solar game itself.

“We’re looking hard at the question of whether we can get into the business ourselves in order to do solar and other forms of renewables on a larger scale,” Darbee says. “Let’s take some of the work that’s been done around solar thermal and see if we can partner with one of the vendors and own larger solar installations on a farm rather than on a rooftop.”

“I like the idea of bringing the balance sheet of a utility, $35 billion in assets, to bear on this problem,” he adds.

It’s an approach taken by the renewable energy arm of Florida-based utility FPL (FPL), which has applied to build a 250-megawatt solar power plant on the edge of the Mojave Desert in California.

For now, PG&E is placing its biggest green bets on solar and wind. The utility has also signed a 2-megawatt deal with Finavera Renewables for a pilot wave energy project off the Northern California coast. Given the power unleashed by the ocean 24/7, wave energy holds great promise, Darbee noted, but the technology is in its infancy. “How does this technology hold up against the tremendous power of the of the Pacific Ocean?”

Electric cars

Darbee is an auto enthusiast and is especially enthusiastic about electric vehicles and their potential to change the business models of both the utility and car industries. (At Fortune’s recent Brainstorm Green conference, Darbee took Think Global’s all-electric Think City coupe for a spin and participated in panels on solar energy and the electric car.)

California utilities look at electric cars and plug-in hybrids as mobile generators whose batteries can be tapped to supply electricity during peak demand to avoid firing up expensive and carbon-spewing power plants. If thousands of electric cars are charged at night they also offer a possible solution to the conundrum of wind power in California, where the breeze blows most strongly in the late evenings when electricity demand falls, leaving electrons twisting in the wind as it were.

“If these cars are plugged in we would be able to shift the load from wind at night to using wind energy during the day through batteries in the car,” Darbee says.

The car owner, in other words, uses wind power to “fill up” at night and then plugs back into the grid during the day at work so PG&E can tap the battery when temperatures rise and everyone cranks up their air conditioners.

Darbee envisions an electricity auction market emerging when demand spikes. “You might plug your car in and say, ‘I’m available and I’m watching the market and you bid me on the spot-market and I’ll punch in I’m ready to sell at 17 cents a kilowatt-hour,” he says. “PG&E would take all the information into its computers and then as temperatures come up there would be a type of Dutch auction and we start to draw upon the power that is most economical.”

That presents a tremendous data management challenge, of course, as every car would need a unique ID so it can be tracked and the driver appropriately charged or credited wherever the vehicle is plugged in. Which is one reason PG&E is working with Google on vehicle-to-grid technology.

“One of the beneficiaries of really having substantial numbers of plug-in hybrid cars is that the cost for electric utility users could go down,” says Darbee. “We have a lot of plants out there standing by for much of the year, sort of like the Maytag repairman, waiting to be called on for those super peak days. And so it’s a large investment of fixed capital not being utilized.” In other words, more electric and plug-in cars on the road mean fewer fossil-fuel peaking power plants would need to be built. (And to answer a question that always comes up, studies show that California currently has electric generating capacity to charge millions of electric cars.)

Nuclear power

Nuclear power is one of the hotter hot-button issues in the global warming debate. Left for dead following the Three Mile Island and Chernobyl disasters, the nuclear power industry got a new lease on life as proponents pushed its ability to produce huge amounts of carbon-free electricity.

“The most pressing problem that we have in the United States and across the globe is global warming and I think for the United States as a whole, nuclear needs to be on the table to be evaluated,” says Darbee.

That’s unlikely to happen, however in California. The state in the late 1970s banned new nuclear power plant construction until a solution to the disposal of radioactive waste is found. PG&E operates the Diablo Canyon nuclear plant, a project that was mired in controversy for years in the ’70s as the anti-nuke movement protested its location near several earthquake faults.

“It’s a treasure for the state of California – It’s producing electricity at about 4 cents a kilowatt hour,” Darbee says of Diablo Canyon. “I have concerns about the lack of consensus in California around nuclear and therefore even if the California Energy Commission said, `Okay, we feel nuclear should play a role,’ I’m not sure we ought to move ahead. I’d rather push on energy efficiency and renewables in California.”

The utility industry

No surprise that Darbee’s peers among coal-dependent utilities haven’t quite embraced the green way. “I spent Saturday in Chicago meeting with utility executives from around the country and we’re trying to see if we can come to consensus on this very issue,” he says diplomatically. “There’s a genuine concern on the part of the industry about this issue but there are undoubtedly different views about how to proceed and what time frames to proceed on.”

For Darbee one of the keys to reducing utility carbon emissions is not so much green technology as green policy that replicates the California approach of decoupling utility profits from sales. “If you’re a utility CEO you’ve got to deliver earnings per share and you’ve got to grow them,” he says. “But if selling less energy is contradictory to that you’re not going to get a lot of performance on energy efficiency out of utilities.”

“This is a war,” Darbee adds, “In fact, some people describe [global warming] as the greatest challenge mankind has ever faced — therefore what we ought to do is look at what are the most cost-effective solutions.”

About Green Wombat

Green Wombat is written by
Todd Woody, a veteran environmental journalist based in California who writes for The New York Times, the Los Angeles Times, Grist and Yale e360. He's one of the few people on the planet who have held a northern hairy-nosed wombat in the wild.

Todd formerly was a senior editor at Fortune magazine, an assistant managing editor at Business 2.0 magazine and the business editor of the San Jose Mercury News.